Pollution of the People

Chemical contamination of water, air and food supplies has been documented for decades, but only recently have scientists begun to uncover details about the industrial pollution of a much more intimate site: our bodies.

It should come as no surprise that industrial chemicals are running through our veins. Industry reported dumping 7.1 billion pounds of hazardous compounds into the air and water in the United States in the year 2000, according to the most recent Toxic Release Inventory, a U.S. Environmental Protection Agency (EPA) program that tracks only a subset of industries.

But not until recently, with advances in the technology of biomonitoring, have scientists been able to accurately measure the actual levels of chemicals in people's bodies.

Now, with the recent release of the largest-ever biomonitoring study by the U.S. Centers for Disease Control and Prevention (CDC), and a new peer-reviewed study by independent researchers, scientists know more than they ever have about a new evolutionary phenomenon: the universal chemical body burden of people.

"This is irrefutable proof that humans carry around scores of industrial chemicals, most of which have never been tested for human health effects," says Jane Houlihan, vice president of research at the Washington D.C.-based Environmental Working Group (EWG), and lead author of one of the studies.

Most of these chemicals did not exist in the environment, let alone in human bodies, just 75 years ago.

The $450-billion chemical industry has responded with assurances that the mere presence of chemicals in people is no proof of harm, but critics say the human population is the unwitting test subject of a dangerous and unprecedented chemical experiment.

Chemical Load

The new CDC National Report on Human Exposure to Environmental Chemicals, released in January, is the largest set of body burden data ever collected in the U.S. and the first time chemical exposure by age, race and sex has been analyzed on a national scale. CDC tested the blood and urine of a nationally representative group of Americans for the presence of 116 toxic chemicals -- all of which were found in people.

"This report is by far the most extensive assessment ever made of the exposure in the U.S. population to environmental chemicals," says CDC Deputy Director Dr. David Fleming. "It's a quantum leap forward in providing objective scientific information about what's getting into people's bodies and how much."

Public health experts say one of the most disturbing findings is that children had higher body burdens than adults of some of the most toxic chemicals, including lead, tobacco smoke and organophosphate pesticides.

"This is a concern because of the potential of toxic chemicals to interfere with development," says Dr. Lynn Goldman, a former EPA official and a professor at the Johns Hopkins University School of Public Health.

Children had double the level of adults of the pesticide chlorpyrifos (known as Dursban) -- a chemical that animal studies indicate has long-term effects on brain development if exposure occurs early in life. Dursban was the most widely used insecticide in the United States until the EPA banned its use in households a year ago, although some uses remain legal. Other organophosphate pesticides, also linked to neurological and nervous system damage in animal studies, remain in widespread use.

Children were also disproportionately exposed to some of the most toxic phthalates, the CDC found. Phthalates -- a class of industrial chemicals used in polyvinyl chloride (PVC) plastic, cosmetics and other consumer products -- cause a spectrum of health effects in animal studies, including damage to the liver, kidneys, lungs and the reproductive system, particularly the testes of developing males.